This is the list of what i have done as far as a tune up.

oil change
air filter
acc. belt
plugs and wires
cleaned MAS

still have to:
change O2 sensor
grease front suspension and drivline
clear computer

My truck has ~130k on it and i have no idea what the previous owner did, so please tell me if there is anything i am missing. Thanks.

flush coolant system and change tranny fluid and filter?

Check the fluid in the differentials.

Clean the throttle body, may want to clean the upper intake- do a search of the site for cleaning the tb and upper intake its there.